The present invention generally relates to support assemblies for panel structures, and particularly to mounting hardware therefor as used in semitrailer vans, truck bodies, cargo boxes, railway freight cars and the like.
The use of lightweight door panels has become increasingly prevalent in the transportation industry to reduce the weight of a vehicle while maintaining structural integrity. Accordingly, it is known to fabricate such door panels of a composite nature including a core material of rigid polystyrene, for example, to which metallic skins are adhesively bonded on each face of the core. Of course, other composite door panels are known such as those having a honeycomb interior which also provides for structural integrity. The skins provide resistance to deflection and resistance to moisture as they are structurally bonded to the core.
Although such door panel structures have received wide acceptability, problems have been encountered in the area of securely attaching hardware, such as hinges or the like, to the door panels. One problem concerns the possibility of excessive compression of the door panels which may be fabricated with somewhat compressible cores such as rigid polystyrene. Excessive compression may also damage such cores as those fabricated of honeycomb constructions.
Another problem concerns the distribution of the hanging forces from hardware to the door panel. Heretofore, it was simple enough to simply drill holes through a relatively rigid door panel, such as one of plywood construction, and attach the hardware by means of conventional bolts. However, with lightweight composite panel constructions as described above, repeated operation of the door panels can result in excessive wear in the area of the bolts which often results in play between the hardware and the door panels. This can cause misalignment of the doors.
The present invention is directed to a new and improved support assembly for attaching hardware to panel structures in order to solve the above and other problems resulting from the use of lightweight composite door panels.